Integrated ultrasonic testing and cathodic protection measurement probe

ABSTRACT

This application discloses integrated probes and probe systems, which can be attached to the robotic arms of a remotely operated vehicle to perform both cathodic protection (CP) voltage measurements and ultrasonic testing (UT) thickness measurements at an underwater surface. In some embodiments, the integrated probe system couples an inner and outer gimbal together such that one or more electrically conductive legs pass from the outer gimbal through the inner gimbal. These legs are arranged about an ultrasonic sensor which extends from the front surface of the inner gimbal. When the integrated probe contacts the underwater surface, both the ultrasonic sensor and at least one leg contact the surface, thereby providing substantially simultaneous CP and UT measurements.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority under 35 U.S.C. § 119 to U.S.Provisional Application Ser. No. 62/395,162, filed Sep. 15, 2016, whichis hereby incorporated by reference in its entirety.

FIELD OF THE INVENTION

This patent application generally relates to testing and measuringmechanisms, and more particularly to probe systems for ultrasonicallymeasuring thickness and performing cathodic protection voltage readingsin an underwater environment.

BACKGROUND

In order to non-destructively measure the thickness of a structure, onecommon practice is to have a measuring device emit ultrasonic waves atthe surface of the structure and to measure the time it takes for theultrasonic wave to return to the measuring device. Ultrasonic testing(“UT”) is applicable for measuring the thickness of metal structures,such as underwater structures like boat hulls, pilings, pipelines, andrisers. In order to limit corrosive effects to such underwater surfaces,the technique of cathodic protection (“CP”) is applied. In CP, the metalsurface of the underwater structure is made into a cathode of anelectrochemical cell (e.g., a Galvanic cell) and the surface is coatedwith another metal having a greater negative electrode potential (e.g.,zinc, magnesium, aluminum) that functions as an anode. Then, the anodicmetal corrodes, but the structure surface does not. To ensure that CP isworking as intended, it is common to measure the voltage at the surfaceof the structure. Typically, for underwater structures, a remotelyoperated vehicle (“ROV”) or human diver is used to perform CP and UTmeasurements. In either case, due to load and logistical limitationsinherent with conventional ROVs, CP and UT measurements are performed bytwo probes at separate ROV robotic arms or by exchanging one probe foranother at a single arm. In either case, the switching or readjusting ofprobes to perform repeated CP and/or UT measurements is time consumingand costly. Additionally, due to the weight of conventional CP and UTprobe systems and the need for a two-armed ROV system, only largerWork-Class ROVs are capable of attaching two arms to alternatinglyperform both measurements in a single trip. However, Work-Class ROVs areunsuitable for shallow and limited accessibility (e.g., surfaces withinsmall cavities) inspection sites. Thus, there is a need for anintegrated CP and UT probe system that can be coupled to smaller andlighter ROVs having only a single robotic arm.

It is in regard to these issues that the present application isprovided.

SUMMARY OF THE INVENTION

According to a broad aspect of the invention, integrated probe systemsare provided that can substantially simultaneously perform both cathodicprotection (CP) voltage readings and ultrasonic testing (UT) thicknessmeasurements.

In accordance with one aspect of the invention, embodiments of theintegrated probe systems include an outer gimbal having a front surfaceand a rear surface, and an inner gimbal coupled to the outer gimbal toprovide at least one degree of freedom. The inner gimbal can include afront surface defining a cavity therein, and the inner gimbal can beshaped to define one or more ingresses that pass crosswise between thefront and rear surfaces of the inner gimbal. In some embodiments, theingresses are defined by the inner gimbal to be indentations formedalong a circumference of the inner gimbal. In other embodiments, theingresses are defined by the inner gimbal to be apertures transverselyformed through the inner gimbal. In one or more embodiments, theintegrated probe system includes an articulated carrier having a firstend integrally formed with the rear surface of the inner gimbal and aball caster disposed at a second end, in which the ball caster couplesto the outer gimbal to provide the at least one degree of freedom to theinner gimbal.

Continuing with this aspect of the invention, in one or moreembodiments, the integrated probe system includes a sensor housingseated in the cavity of the inner gimbal. An ultrasonic probe is withinthe sensor housing, the ultrasonic probe having a transducer crystal anda flexible membrane arranged about the transducer crystal, and acouplant disposed within a gap between the flexible membrane and thetransducer crystal. Further, one or more legs, which each have anelectrically conductive tip and a subsea housing containing a referenceelectrode, extend longitudinally away from the outer gimbal via the oneor more ingresses and are arranged about the ultrasonic probe, such thatthe one or more legs are passively adjustable in response to a forceimparted when the one or more legs contact the underwater surface.

In accordance with another aspect of the invention, embodiments of theintegrated probe system include an ultrasonic sensor body, an ultrasonictesting cable disposed at a first end of the ultrasonic sensor body, andan ultrasonic probe disposed at a second end of the ultrasonic sensorbody. In one or more embodiments, the ultrasonic probe includes anultrasonic element and a flexible membrane adjacently spaced about theultrasonic sensor body to define a gap between the ultrasonic elementand the flexible membrane, in which the gap is filled with a couplant.Further, the integrated probe system can include a housing that definesan aperture therethrough, in which the aperture is centrally located inthe housing and in which the ultrasonic probe is seated in the aperture,and the housing further including an electrically conductive portion.Additionally, the integrated probe system includes conductive leadsconnected to and extending from the electrically conductive portion.

In accordance with a further aspect of the invention, embodiments of asystem for performing cathodic protection voltage readings andultrasonic testing thickness measurements at an underwater surfacesubstantially simultaneously are provided. The system includes aremotely operated underwater vehicle having a measuring arm, with an endeffector disposed at a free end of the measuring arm. Additionally, thesystem includes an integrated probe for measuring cathodic protectionvoltage and ultrasonic testing thickness measurement coupled to the endeffector. In one or more embodiments, the integrated probe includes anouter gimbal having a front surface and a rear surface, and an innergimbal coupled to the outer gimbal to provide at least one degree offreedom. The inner gimbal has a front surface that defines a cavitytherein, and the inner gimbal is shaped to define one or more ingressesthat pass crosswise between the front and rear surfaces of the innergimbal. The integrated probe further includes a sensor housing seated inthe cavity of the inner gimbal, and an ultrasonic probe disposed withinthe sensor housing, in which the ultrasonic probe includes a flexiblemembrane arranged about a transducer crystal such that a gap is definedtherebetween and filled with a couplant. Further, a voltage electrode iscommunicatively coupled to a reference electrode, in which the voltageelectrode is disposed at the end effector or the integrated probe, andthe reference electrode is disposed within the remotely operatedunderwater vehicle.

In accordance with an additional aspect of the invention, embodiments ofa method of performing cathodic protection voltage readings andultrasonic testing thickness measurements on an underwater surface withan integrated probe having an ultrasonic probe and at least one leg withan electrically conductive tip are provided. The method includespositioning a remotely operated vehicle, which has at least one roboticarm with an arm end effector disposed at a free end of the robotic armand the integrated probe coupled to the arm end effector, in proximityto the underwater surface. The method then includes contacting theunderwater surface with the integrated probe and orienting theintegrated probe transverse to the underwater surface such that theultrasonic probe and the at least one leg with an electricallyconductive tip contacts the underwater surface. Then, the methodcontinues by measuring, by the at least one leg, a voltage at theunderwater surface, and measuring, by the ultrasonic probe, a thicknessof the underwater surface. Further, in one or more embodiments, themethod then includes processing, by a signal conditioner housed withinthe remotely operated vehicle, the voltage and the thickness of theunderwater surface to produce a data file. The method continues bytransmitting the data file to a data acquisition unit housed within theremotely operated vehicle. Additionally, the method includes processing,by the data acquisition unit, the data file to record, review, oranalyze the voltage and thickness of the underwater surface.

In accordance with a still further aspect of the invention, embodimentsof the integrated probe systems include a probe carrier that has atleast one degree of freedom relative to a static base, and a rearsurface coupled to the static base and a front surface having anelectrically conductive portion and defining a cavity therein. Further,the electrically conductive portion can include one or more legsarranged about the ultrasonic probe, each leg having an electricallyconductive tip and a subsea housing containing a reference electrode,and which extend longitudinally away from the probe carrier, in whichthe one or more legs are passively adjustable in response to a forceimparted when the one or more legs contact the underwater surface. Inone or more embodiments, the integrated probe systems include a sensorhousing seated in the cavity of the probe carrier and an ultrasonicprobe disposed within the sensor housing, the ultrasonic probe having atransducer crystal and a flexible membrane arranged about the transducercrystal, and a couplant disposed within a gap between the flexiblemembrane and the transducer crystal.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawing figures illustrate exemplary embodiments andare not intended to be limiting of the invention. Among the drawingfigures, like references are intended to refer to like or correspondingparts.

FIG. 1A illustrates a front view of an integrated CP and UT probe systemin accordance with at least one embodiment of the present application;

FIG. 1B illustrates an isometric side view of the integrated CP and UTprobe system of FIG. 1A;

FIG. 2A illustrates a front view of an integrated CP and UT probe systemin accordance with an alternate embodiment of the present application;

FIG. 2B illustrates a side view of the alternate probe system of FIG.2A;

FIG. 3A illustrates a top cutaway view of an integrated CP and UT probein accordance with another alternate embodiment of the presentapplication;

FIG. 3B illustrates an isometric side view of the integrated CP and UTprobe of FIG. 3A;

FIG. 4 illustrates a perspective view of an integrated CP and UT probesystem in connection with a robotic arm in accordance with anotheralternate embodiment of the present application; and

FIG. 5 is a simplified schematic diagram illustrating a side view of aninspection system implementing an integrated CP and UT probe systemattached to an ROV in which the CP reference electrode and the CPvoltage probe are split between the probe and the ROV body in accordancewith at least one embodiment of the present application.

DETAILED DESCRIPTION OF CERTAIN EMBODIMENTS OF THE INVENTION

The invention is now described with reference to the accompanyingdrawings, which form a part hereof, and which show, by way ofillustration, example implementations and/or embodiments of the presentinvention. It is to be understood that other embodiments can beimplemented and structural changes can be made without departing fromthe spirit of the present invention. Among other things, for example,the disclosed subject matter can be embodied as methods, devices,components, or systems.

Furthermore, it is recognized that terms may have nuanced meanings thatare suggested or implied in context beyond an explicitly stated meaning.Likewise, the phrase “in one embodiment” as used herein does notnecessarily refer to the same embodiment and the phrase “in anotherembodiment” as used herein does not necessarily refer to a differentembodiment. It is intended, for example, that claimed subject matter canbe based upon combinations of individual example embodiments, orcombinations of parts of individual example embodiments.

In accordance with the present application, embodiments are providedthat are directed to integrated probes and integrated probe systems formeasuring cathodic protection (CP) voltage and measuring surfacethickness using ultrasonic testing (UT) in which the delay betweentaking each measurement is minimized. In this way, CP and UTmeasurements can be performed substantially simultaneously. For example,both CP and UT measurements can be performed during a single touchdownat a specific underwater surface (or an “inspection surface”), such asan underwater pipeline or piling, or the underside of a moored shiphull.

In one aspect, the integrated probes as provided in one or moreembodiments herein can be coupled to a single robotic arm of a remotelyoperated vehicle (ROV) at, for example, the free end of an arm-endeffector. The structural limitations of typical ROVs restrict theirrobotic arms to only a single interchangeable or permanently mountedprobe per robotic arm, and such arms lack the dexterity necessary toperform simultaneous CP and UT measurements. Thus, conventionally, inorder for a ROV to perform both CP and UT measurements in a single trip,it must have at least two robotic arms. Each robotic arm is heavy, andonly large, work-class ROVs can include two or more robotic arms. Insome cases, conventional measurement methods require a complete probeexchange (e.g., from CP to UT, or vice versa) at the arm to perform thesecond measurement. Such limited actuation capabilities result ininherent delay (and thus increased costs due to necessarily increasedROV time) because the two probe measurement systems must switch betweentwo wholly separate CP and UT probes, and must reorient the second probeto the same inspection surface where the first probe measurement wastaken. The present application does not require the implementation oftwo separate CP and UT probes or probe systems by separate robotic armsof a ROV or by requiring the exchange of probe attachments.

Further, the integrated probe systems herein provide the advantage ofbeing implementable by small, lightweight class ROVs having only asingle robotic arm, such as electric ROVs, general class ROVs,inspection class ROVs, and observation class ROVs. Smaller class ROVscan be necessary if the inspection surface has accessibility issues(e.g., shallow water sites), or if there are power supply limitations.

In one or more embodiments, the integrated probe system includes acentral UT sensor or transducer (e.g., a piezo-ceramic crystal) with asurrounding array of electrically conductive legs having tips orfixtures that are articulated and passively adjustable. The electricallyconductive legs are not rigid, but rather have some flexibility withrespect to how they contact an underwater surface. In this way, when theelectrically conductive legs contact an underwater surface, theypassively adjust to orient the UT sensor transverse to the inspectionsurface. At the same time, the legs conduct the cathodic protectionelectrical voltage associated with the surface, such as withelectrically conductive steel tips, thereby acting as a CP probe. Inthis way, CP and UT measurements can be conducted substantiallysimultaneously, thereby reducing measurement inspection time, the sizeand weight added to the robotic arm, and improving ROV agility.

Referring now to FIGS. 1A-B, an integrated probe system 100 forconducting cathodic protection voltage readings and ultrasonic testingthickness measurements at an underwater surface in accordance with oneor more implementations of the present application is provided.Integrated probe 100 includes an outer gimbal 105 that functions as abase mount for coupling to a robotic arm. For example, the rear surfaceof the outer gimbal 105 can be coupled to a ROV measurement arm at anend effector or other static base, as is known in the art. The outergimbal 105 is generally cylinder shaped, though rectangular, ellipsoidor other shapes can be implemented as appropriate. The outer gimbal 105can be made of stainless steel or other alloy that is suitable forunderwater inspection.

In one or more embodiments, an inner gimbal 110 is coupled to the outergimbal 105. For example, the inner gimbal 110 is coupled to the outergimbal 105 by one or more of: screws, threads, bolts, adhesives, maleand female coupling members, joints, diaphragm coupling, ball andsocket, cam and groove coupling or the like. The inner gimbal 110 can bemade of stainless steel or other alloy that is suitable for underwaterinspection. Preferably, the inner gimbal 110 is molded to define one ormore ingresses 115 a, 115 b, 115 c, 115 d (and more generally ingresses115), for one or more electrically conductive legs 130 to pass throughor around the circumference of the inner gimbal. The electricallyconductive legs 130 act as cathodic protection voltage electrodes. Inone or more embodiments, the ingresses 115 a, 115 b are defined asindentations formed along a circumference of the inner gimbal 110, in aconcave, rectangular, triangular, or other shape designed to facilitatethe passive adjustment of legs 130. In one or more embodiments, theingresses 115 c, 115 d are defined as apertures formed through thenarrow, crosswise width of inner gimbal 110. For example, theaperture-type ingresses 115 c, 115 d can be a cross-section of the innergimbal 110. Integrated probe 100 can also include a combination ofindentation-type ingresses 115 a, 115 b and aperture-type ingresses 115c, 115 d. In this way, different arrangements of the ingresses 115 andlegs 130 defined by inner gimbal 110 can be contemplated that are moresuitable for passively adjusting to a particular inspection surface.Moreover, the passage of the legs 130 through the ingresses 115 canserve to couple the inner gimbal 110 to the outer gimbal 105 in someembodiments.

A sensor housing 120 is implanted at the front surface of the innergimbal 110 and depends at least partially beyond the front surface. Inone or more embodiments, the sensor housing 120 is implanted at thefront surface of the inner gimbal 110 in a cavity defined therein. Forexample, the sensor housing 120 can include a knurled ring made ofstainless steel or other alloys, a flexible membrane and a locking ringconnected in sequence. In one or more embodiments, the sensor housing120 is located at the center of the inner gimbal 110. In one or moreembodiments, the sensor housing 120 is located on a circumferential edgeof the outer gimbal 105 or inner gimbal 110. An ultrasonic probe 125 iscontained within the sensor housing 120 and arranged below the flexiblemembrane. In one or more embodiments, the ultrasonic probe 125 comprisesa single piezo-ceramic crystal. In another embodiment, the ultrasonicprobe 125 comprises a plurality of piezo-ceramic crystals. Theultrasonic probe 125 can be selected to emit and receive ultrasonicwaves at a variety of particular frequencies. For example, theultrasonic sensor can operate at frequencies of 2.0 MHz, 2.25 MHz, 3.5MHz, 5.0 MHz, or 7.5 MHz. To facilitate ultrasonic transmission, a filmof membrane couplant is located, for example, within a gap between theultrasonic probe 125 and the flexible membrane of the sensor housing120. Membrane couplant can comprise a viscous liquid, gel, or paste usedto minimize the amount of air in the gap between the sensor and themembrane. For example, the membrane couplant can be propylene glycol,glycerin, silicone oil, or various commercially available gels.

The CP probe functionality of the integrated probe system 100 isprovided by measuring the voltage difference between one or morereference electrodes (or “reference cells”) and one or more voltageelectrodes that contact the inspection surface. The reference electrodeis kept electrically insulated from the voltage electrode and istypically submerged in water (such as the underwater environmentitself). In one or more embodiments, CP probe functionality of theintegrated probe system 100 is provided by one or more electricallyconductive legs 130 that extend longitudinally beyond the front surfaceof the outer gimbal 105. The legs 130 can be integrally formed with theouter gimbal 105 or can be separate cathodic probes that are installedat the outer gimbal. In either case, the legs are articulated—i.e.,connected to allow flexibility of movement. In one or more embodiments,the one or more legs 130 pass through one or more ingresses 115 definedby the inner gimbal 110. In one or more embodiments, the legs 130include a subsea housing 131 that contains one or more reference cellswithin that serves as a reference electrode, and a conductive tip 132 atthe end of the housing that serves as a voltage electrode. Theconductive tip 132 is made of conductive metals, such as steel or otheralloys that can conduct voltage at the underwater surface to bemeasured. The reference cell housed in the subsea housing 131 must beexposed to water and can be of the type used in conventional cathodicprotection potential probe construction, such as a silver/silverchloride half cell or a pure zinc electrode. In other embodiments, thereference electrode is located at the outer surface of, or housedwithin, a ROV or its robotic arm. The electrically conductive legs 130are in electrical connection with a voltage processing device, such as avoltmeter (not shown), which can be located at the integrated probesystem 100, an ROV or surface-side in order to record and/or displayvoltage readings taken at a measurement site. In embodimentsimplementing an ROV, the ROV can have an umbilical cable leading to anabove-surface location to couple, by an electrical cable, a voltmeter tothe non-tip end of the legs 130, such that when the conductive tip 132contacts the underwater surface (e.g., a pipeline), the potential ismeasured by the voltmeter. At least one voltage electrode at one of thetips 132 of legs 130 must be in contact with the inspection surface toobtain an accurate cathodic potential reading, but it is not necessarythat each leg 130 be in contact with the inspection surface when thereading is made. The present application does not suffer from inaccuratereadings due to various resistive paths presented by each leg 130 duringvoltage reading.

In one or more embodiments, the tips 132 of legs 130 are shaped as coneshaving circular or elliptical bases. In other embodiments, the tips 132of legs 130 are pyramid shaped, rectangular prisms, semicircular,pointed, flat, or have rounded ends. In this way, the tips 132 arere-configurable or interchangeable to achieve various contactconfigurations. For example, the tips 132 can be mobile metallicrollers, wheeled tips or ball casters instead of static stainless steeltips. Such a configuration will reduce impact on a ROV arm end effectorupon touchdown at an inspection surface (e.g., a steel surface of apipe) and allow for translational motion across the inspection surfacewhen performing scans instead of spot checks.

During operation of integrated probe system 100, in order to performboth CP and UT measurements substantially simultaneously, both the CPand UT aspects of the integrated probe system need to be brought intoproximity to the inspection surface. Sufficient proximity is dependentupon the calibration of the ultrasonic probe 125, meaning that theultrasonic probe has a certain effective measurement range as a resultof the properties of water in between the probe and the surface, thematerials of the surface, and other considerations. For example, theeffective measurement range of the ultrasonic probe 125 means that itneeds to abut or be within a few millimeters of the inspection surfaceto perform a successful measurement. If the ultrasonic probe 125 is anyfurther from the inspection surface, it will lose signal integrity andfail to acquire a reading. In one or more embodiments, the ultrasonicprobe 125 has an effective measurement range of 0-2 mm. The further thatthe ultrasonic probe 125 is from the inspection surface, the lessaccurate that the UT measurement is. In one or more embodiments, theelectrically conductive legs 130 must contact the inspection surface inorder to take a CP voltage measurement. As such, integrated probe system100 can be arranged such that the legs 130 contact the inspectionsurface while ultrasonic probe 125 is positioned within its measurementeffectiveness range (e.g., 0-2 mm from the inspection surface). Thearrangement of legs 130 with regard to the ultrasonic probe 125 withinthe sensor housing 120 can be configured to accommodate the diameter orcurvature of particular inspection surfaces. For example, in one or moreembodiments, the legs 130 extend a distance beyond the sensor housing120. In this way, when the integrated probe system 100 is brought inproximity to the inspection surface, one or more of the legs 130 willcontact the surface, but the ultrasonic probe 125 will not, though theultrasonic probe will still be close enough to the surface to be withinits effective measurement range for performing accurate UT measurements.In one or more embodiments, the legs 130 extend 0.5 mm, 1 mm, 1.5 mm, 2mm, or 2.5 mm beyond the sensor housing 120. In other embodiments, thelegs 130 are aligned with the sensor housing 120. Longer legs 130 can beimplemented for inspection surfaces having smaller diameters (e.g.,approximately 10 cm or less) because for smaller inspection surfaces,the front surface width of the integrated probe system 100 is comparableto the inspection surface and thus not all the legs can contact thesurface at once, though if at least one leg contacts the surface and theother legs are oriented to surround the surface, then the ultrasonicprobe 125 will be oriented at the inspection surface within itseffective measurement range.

The decision of whether and how much the legs 130 extend beyond thesensor housing 120 and where to arrange the legs at the front surface ofthe integrated probe system 100 can be dependent upon the particulararrangement desired. For example, the legs 130 can be advantageouslyarranged around a sensor housing 120 located in the center of the frontsurface of inner gimbal 110, such that each leg 130 is equidistant fromboth one another and the sensor housing. Centrally locating the sensorhousing 120 in this way maximizes the likelihood that a UT thicknessmeasurement is performed as one or more of the legs 130 contacts aninspection surface. The distance that the legs 130 are from the sensorhousing 120 can be varied, depending on the arrangement desired toinspect a particular surface. For example, an arrangement in which thelegs 130 are near to the sensor housing 120 decreases any differences inmeasurement lag between taking a CP voltage and UT thickness measurementand increases the precision of the spot inspection, whereas spacing thelegs 130 relatively further from the sensor housing provides a widerinspection area and can provide an alignment assist (i.e., one legcontacts the surface and the inner gimbal 110 shifts in response to thatforce, thereby pushing one or more other legs into contact as well).

While the exemplary embodiments described herein include CP probes thatare arranged to contact the inspection surface to perform voltagemeasurements, the invention is not limited to express contact CP probetypes, such as legs 130, but can include non-contacting proximity CPprobes. For example, a proximity CP probe can be implemented at theinner gimbal 110 in place of the legs 130. A proximity electrode ishoused at the inspection tip of the proximity CP probe and a referenceelectrode is provided in the form of a “ground” wire that connects tothe voltmeter (e.g., within an ROV or diver umbilical cord). A proximityCP probe typically has an effective measurement range on par with theultrasonic probe 125 (e.g., 0-1 mm, 0-1.5 mm, 0-2 mm).

In one aspect of the present application, the integrated probe system100 provides an advantage of being passively adjustable to theunderwater surface to be measured. As such, one or more rotationaljoints 135 can be included in integrated probe system 100 to providefreedom of movement for the outer gimbal 105, the inner gimbal 110and/or the electrically conductive legs 130. The rotational joints 135can be hinged to the outer gimbal 105, the inner gimbal 110 or betweenthe two. When the rotational joint 135 is hinged at a first end to theouter gimbal 105, the second end (i.e., the free end) of the rotationaljoint is coupled to a ROV measurement arm, static base or other externalcarrier (such as an arm end-effector). In one or more embodiments, therotational joints 135 include two rotational joints that couple theouter gimbal 105 to an external carrier and two rotational joints thatcouple the inner gimbal 110 to the outer gimbal 105. The rotationaljoints 135 serve to effectively provide a combined two degrees offreedom to the ultrasonic probe 125, namely for the outer gimbal 105 topitch around the side-to-side axis defined by a plane in thelongitudinal diameter of the outer gimbal (the “pitch plane”) and forthe inner gimbal to 110 yaw around the vertical axis defined by a planeperpendicular to the longitudinal diameter of the outer gimbal (the “yawplane”).

In practice, when the electrically conductive legs 130 contact theinspection surface, the force imparted from the surface acts on theintegrated probe system 100 to push a contacting leg or legs back andbring other legs into contact with the surface. In this way, additionallegs 130 can be brought into contact with the inspection surface,thereby providing more accurate voltage measurements. The certainangular motion in the pitch and yaw planes provided by the arrangementof the rotational joints 135 of the integrated probe system 100 servesto improve leg 130 surface contact. For example, in one or moreembodiments, the integrated probe system 100 can adjust by 0-15, 0-20,0-30, or 0-45 degrees through the pitch or yaw planes.

In a particular embodiment illustrated by FIGS. 1A-1B, four articulatedelectrically conductive legs 130 are arranged around an ultrasonic probe125. FIG. 1B illustrates a first pair of legs 130 a, 130 b that arediametrically opposed to one another and pass through indentation-typeingresses 115 a, 115 b defined by inner gimbal 110. A second pair oflegs 130 c, 130 d is also diametrically opposed to one another andpasses through aperture-type ingresses 115 c, 115 d defined by thecircumferential edge of inner gimbal 110. In this embodiment, the fourlegs 130 a-130 d are equally spaced 90 degrees apart about theultrasonic probe 125. This arrangement provides maximum range for atleast one leg to be able to contact the inspection surface in order toobtain a voltage reading. However, depending on the particularapplication, other electrically conductive leg arrangements of four legscan be contemplated in which the legs are not equally spaced apart.

Furthermore, the flexibility of legs 130 in conjunction with theflexibility of inner gimbal 110 causes the ultrasonic probe 125 to bealigned on the inspection surface within a certain margin (e.g., thefront surface of inner gimbal 110 is substantially transverselyperpendicular to the target surface). This passive alignment of theultrasonic probe 125 by the electrically conductive legs 130 allows bothCP voltage and UT measurements to be performed simultaneously, or atleast in a single probing of the inspection surface. In one or moreembodiments, a proximity sensor is coupled with the ultrasonic probe 125to aid in positioning at the inspection surface. For example, theproximity sensor can be an infrared or acoustic sensor located insidesensor housing 120 at or adjacent to the flexible membrane of ultrasonicprobe 125.

With reference now to FIGS. 2A-B, an integrated probe system 200 forconducting cathodic protection voltage readings and ultrasonic testingthickness measurements at an underwater surface in accordance with oneor more implementations of the present application is provided.Integrated probe 200 comprises two main components which interlocktogether in such a way as to provide freedom of movement to theintegrated probe to, upon contact, passively orient itself transverse tothe inspection surface. An extruded outer gimbal 205 (or “static base”)comprises the first component and its rear surface can be coupled to anROV measurement arm. The extruded outer gimbal 205 includes a c-channelgroove 206 centrally formed at the front surface of the outer gimbal,the groove having a mouth 208 and a pair of lips 209 a, 209 b that aresized and shaped for coupling the second component of integrated probe200.

The second component includes a series of elements which are coupledtogether or integrally formed such that the combination acts as a singlecomponent that can couple to the outer gimbal 205. The second componentcan also be known as a probe carrier. A probe carrier describes thestructure that houses the ultrasonic probe and provides electricallyconductive material (e.g., electrically conductive voltage electrodes inthe form of legs, a rim, or a surface) that encompass the CP and UTmeasuring tools that are oriented toward an inspection surface. In oneor more embodiments, a probe carrier includes the elements of theintegrated probe systems provided herein that have at least one degreeof freedom of movement, and typically have two degrees of freedom (i.e.,pitch and yaw). FIG. 2B illustrates one particular arrangement ofelements which comprise the second component and its interlocking natureto the outer gimbal 205. In one or more embodiments, a ball caster 217is provided that is sized and shaped to couple with the c-channel groove206. The ball caster 217 shown in FIG. 2B, by way of example, issubstantially spherical, though oval, ellipsoid, rectangular, square orother shapes can be contemplated. In one or more embodiments, the ballcaster 217 is integrally formed with a first end of an articulatedcarrier 219. For example, the articulated carrier 219 and ball caster217 can be a single metallic component made of stainless steel. In otherembodiments, the ball caster 217 and articulated carrier 219 areseparable components that can be coupled or decoupled for easyreplacement. In one or more embodiments, a second end of articulatedcarrier 219 is integrally formed with the rear surface of inner gimbal210 as a single molded piece. In other embodiments, the articulatedcarrier 219 and inner gimbal 210 are separate components that can becoupled or decoupled for easy replacement. In one or more embodiments,the articulated carrier 219 is conical, in which the broader end thatconnects to the inner gimbal 210 tapers toward the end that connects tothe ball caster 217.

Advantageously, the groove 206 and the ball caster 217 flexibly couplesuch that the ball caster has some freedom of movement. In other words,after the ball caster 217 passes into mouth 208 to couple with outergimbal 205, the ball caster 217 is not rigidly fixed in place, butrather can pivot within groove 206 subject to frictional forces at theinner walls of the groove. Further, the conical nature of thearticulated carrier 219 allows the inner gimbal 210 to pivot accordinglywith ball caster 217 in order to orient the front surface of the innergimbal to the inspection surface. Thus, as the inner gimbal 210 contactsan inspection surface, the force imparted by the surface causes theinner gimbal to self-adjust until one or more electrically conductivelegs 230 contact the inspection surface. The one or more electricallyconductive legs 230 extend longitudinally away from the front surface ofinner gimbal 210 and act as a voltage electrode to provide CP probefunctionality. A corresponding reference electrode is electricallyinsulated and incorporated in integrated probe system 200, such aswithin outer gimbal 205, located at an outer surface of or within a ROVor its robotic arm, or in a subsea housing portion of the legs 230, invarious embodiments. In some embodiments, the legs 230 are integrallyformed with inner gimbal 210. For example, the inner gimbal 210 and legs230 can be a single molded piece made of the same or similar material,such as stainless steel. In other embodiments, the legs 230 couple intoingresses defined by the molding of inner gimbal 210 and/or articulatedcarrier 219 (e.g., ingresses 115). In this way, the legs 230 can bereplaceable and can be coupled or decoupled from integrated probe 200for easy replacement. In one or more embodiments, the legs 230 aresimilar or the same as legs 130, and can be entirely electricallyconductive, or can be limited to electrically conductive tips with anon-conductive coupling portion to the inner gimbal 210 (e.g., sub-seahousing 131 and tips 132). This arrangement of elements in the secondcomponent provides CP probe function for measuring surface voltage tointegrated probe 200.

Integrated probe 200 further includes a sensor housing 220 andultrasonic probe 225, which can be the same or similar to sensor housing120 and ultrasonic probe 125. These elements function in concert toprovide UT thickness measurement capabilities to integrated probe 200.In one or more embodiments, the sensor housing 220 is centrally locatedat the front surface of the inner gimbal 210. The legs 230 are thenarranged about the sensor housing in an array such that when one or moreof the legs contact the inspection surface, the ultrasonic probe 225 canperform UT thickness measurements. UT thickness measurements requirethat the ultrasonic probe 225 be in proximity with the inspectionsurface, so each of the legs 230 can only extend a short distance, if atall, beyond the sensor housing 220. For example, the ends of the legs230 can extend 5-10 mm beyond the inner gimbal 210 than sensor housing220 does.

In one exemplary embodiment, three electrically conductive legs areequally spaced in an array around ultrasonic probe 225. For example,each leg can be 120 degrees apart. In this embodiment, the ball caster217 and the articulated carrier 219 provide two degrees of freedom tothe inner gimbal 210 about two perpendicular axes, namely a verticalaxis defined by the plane passing through the diameters of leg 230 a andsensor housing 220, and a horizontal axis defined by the planeperpendicular to the vertical axis and also passing through a diameterof sensor housing 220. These axes can be similar or the same as thepitch plane or yaw plane identified above.

As described elsewhere herein, an underwater ultrasonic probe can becontained in sensor housing having a flexible membrane installed betweena piezo-ceramic (or “transducer”) crystal and the outer surface of theultrasonic sensor housing. In one or more embodiments, electricallyconductive media can be integrated into the rim or other parts of thesensor housing to provide CP probe function. The remainder of the sensorhousing can be made of non-conductive material. In this way, anultrasonic testing thickness measurement probe can function as anintegrated CP/UT probe. In one or more embodiments, such integratedCP/UT probes can be installed in broader integrated probe systems. Forexample, an integrated CP/UT probe of this type can be installed inintegrated probe system 100 or integrated probe system 200.

With reference now to FIGS. 3A-B, an integrated probe 300 for conductingsimultaneous cathodic protection voltage readings and ultrasonic testingthickness measurements at an underwater surface is provided. Integratedprobe 300 includes a sensor body 305 with an ultrasonic testing cable310 coupled at a first end of the sensor body. The ultrasonic testingcable 310 provides data transfer of ultrasonic thickness measurements toa data processing system, which can be within a ROV or surface-side. Anactive ultrasonic element 315 is disposed at a second end of the sensorbody 305, the second end being the end oriented toward the inspectionsurface. In one or more embodiments, ultrasonic element 315 is one ormore piezo-ceramic crystals that emits and receives ultrasonic waves ata particular frequency. For example, the ultrasonic element 315 canoperate at frequencies of 2.0 MHz, 2.25 MHz, 3.5 MHz, 5.0 MHz, or 7.5MHz.

A flexible membrane 320 is adjacent to and spaced from the activeelement 315, thereby defining a gap 325 there between that is filledwith couplant. The couplant can be a viscous liquid (e.g., water), gel,or a paste. In one embodiment, the flexible membrane 320 is made oflatex rubber. The membrane 320 can be connected to sensor body 305 and ahousing 330 of integrated probe 300 in various ways. For example, inresponse to manual urging, the membrane 320 can flex into a biased statewith a reduced profile (e.g., a compression) in order to pass into amouth defined by the housing 330, and upon release of the applied forceat the membrane, the membrane restores to an unbiased state in whichlips formed at the edges of the membrane engage with the interior of thehousing and also engage with the exterior surface of sensor body 305. Inone or more embodiments, the lips of the membrane 320 are sized andshaped to interlock with seats or grooves formed on the interior of thehousing 330 of integrated probe 300. Depending on the resistance of theflexible membrane 320 to compression, in the unstable compressed state,the free ends will urge a greater or lesser amount toward the unbiasedstate. When attached to the interior of housing 330, this urging createsfriction between the inner walls of the housing and the sensor body 305,which prevents the flexible membrane 320 from sliding longitudinallyalong the housing interior once coupled. This friction remains becausethe flexible membrane 320 is unable to fully return to its unbiasedstate while positioned within the groove or seat between the housing 330and the sensor body 305, while the elastic restoring force continuallyapplies pressure on the side walls of the groove. The housing 330circumferentially surrounds at least a portion of sensor body 305. Inone or more embodiments, the housing 330 is screwed onto the sensor body305 via grooves on the inner surface of the housing 330 that receivecorresponding threads molded onto the outer surface of the sensor body305. In one or more embodiments, the housing is cylindrical and ringshaped to define an aperture therethrough in which the flexible membrane320 passes.

In one or more embodiments, the housing 330 provides cathodic protectionvoltage probe functionality by acting as a voltage electrode. Acorresponding reference electrode can be attached to an outer surface ofor within a ROV or its robotic arm (not shown), in an electricallyinsulated manner, in various embodiments. In other embodiments, thereference electrode can be mounted within or to integrated probe 300.For example, the reference electrode can be housed within the sensorbody 305, so long as it is electrically insulated from the voltageelectrode (e.g., housing 330, rim 340, described below). Upon contactwith an inspection surface, the housing 330 conducts the CP voltage ofthe surface to be inspected to a voltage measurement device (e.g., atthe ROV or surface-side) via CP cable 335. CP cable 335 includes one ormore conductive leads connected to and extending from an electricallyconductive portion at the front surface (i.e., the surface orientedtoward the inspection surface). This can be accomplished in two ways. Inone or more embodiments, the entirety of the housing 330 can be made ofconductive material, such as, for example, a knurled ring made ofstainless steel or other alloys. This ensures that a voltage measurementcan be made wherever the integrated probe 300 touches the inspectionsurface. In one or more alternate embodiments, the outer surface (or“rim”) of the housing 330 can be limited to conductive material. In oneor more embodiments, the rim is located adjacent to the flexiblemembrane 320 such that when the membrane contacts the inspectionsurface, the rim contacts simultaneously. For example, FIG. 3Billustrates a rim 340 that includes conductive material along theentirety of the surface surrounding the flexible membrane 320. It shouldbe understood from the preceding discussion that the flexible membrane320 is flush with the rim 340 or, if the membrane extends a distancebeyond the rim, it can compress to enable the rim to make direct contactwith an inspection surface in order to perform a CP measurement at thesame time as a UT measurement. Embodiments of the integrated probe 300do not include flexible membrane 320 designs that prevent the CP probeportion (e.g., housing 330, rim 340) from contacting the inspectionsurface.

With reference now to FIG. 4, an integrated probe system 400 accordingto one or more embodiments is provided. A remotely operated vehicle(ROV) (not shown) includes at least one robotic measuring arm 405 havinga rotatable end effector 410 at the free end of the robotic arm. The endeffector 410 includes one or more probe attachment points for couplingvarious probe attachments. The attachment points can include modularframes that the probe attachment screws or snaps into, or include pointsfor direct fixation to the end effector via a screw and threaded sleeve.Other similar attachment mechanisms can be used, as is known in the art.

The exemplary embodiment in FIG. 4 includes two diametrically opposedattachment points comprising modular frames 411, 412 sized and shaped toreceive an integrated probe system, e.g., integrated system 100,integrated system 200. In other embodiments, the attachment points areseparated by a certain angle, for example, 15, 30, 45, 60, 75 or 90degrees. In one or more embodiments, a cathodic protection (CP) voltagemeasurement probe 415 and an ultrasonic thickness (UT) measurement probe420 are coupled to the modular frames 411, 412 at the attachment points.In one embodiment, a combined CP and UT probe or probe system (e.g.,integrated probe system 100, integrated probe system 200, integratedprobe 300) is coupled to a single attachment point.

A motor (not shown) is housed within or mounted to the robotic arm 405or end effector 410 in order to rotate the attachment points intodesired positions. For example, the motor can be housed within the tipof the robotic arm 405 and be in mechanical connection with the endeffector 410, as is known in the art. By actuating the motor and therebyrotating the end effector 410, the sensor facing the inspection surfacecan be swapped. For example, a ROV can bring the integrated probe system400 into proximity with an inspection surface such that the CP probe 415is oriented transversely to the surface to make a voltage reading.Thereafter, the motor rotates the CP probe 415 out from the inspectionpoint and rotates the UT probe 420 in that same location to make a UTthickness measurement. After the UT thickness measurement is made, themotor can rotate the CP probe 415 and UT probe 420 back into theiroriginal pre-measurement positions. This cuts down on the delay betweenmaking CP and UT measurements.

In one or more embodiments, the rotation of either CP probe 415 or UTprobe 420 occurs automatically as a result of software implementationidentifying that a measurement has been made or is about to be made. Forexample, as soon as a CP voltage reading is complete, a computing devicehaving a processor, which can be located with the housing of the ROV orlocated above-surface and communicatively coupled to the ROV, implementsprogram code stored in a memory to instruct the motor to automaticallyshift the UT probe 420 into the location where the CP probe 415 had justmade a measurement, without human intervention. In this way, the delaybetween taking a CP voltage reading and a UT thickness measurement canbe reduced during underwater surface inspection.

While the exemplary embodiment disclosed in FIG. 4 contemplates a CPprobe 415 and UT probe 420, other inspection sensors can be added inaddition to the CP and UT probes or interchangeably fitted around thecircumference of the actuated end effector 410 at the one or moreattachment points in a modular fashion. For example, other sensors caninclude non-destructive testing sensors like eddy current or ACFMsensors, and visual sensors such as cameras or flashlights. Theinstallation of visual sensors such as a camera with a flashlight on thebody of the integrated probe aids in arm actuation control, therebyproviding a more accurate alignment to the desired inspection surface.

With reference now to FIG. 5, a system 500 for performing cathodicprotection voltage readings and ultrasonic testing thicknessmeasurements at an underwater surface is provided. In the example system500, an integrated CP and UT probe system 505 is provided as describedelsewhere herein (e.g., integrated probe system 100, integrated probesystem 200, etc.), having a CP probe 510 and an UT probe 515. Theintegrated probe system 505 is coupled to a robotic arm 525 of a ROV 520at an arm end-effector 527 located at the free end of the robotic arm.The ROV 520 can be any conventional ROV as is known in the art,including lighter, non-Work-Class ROVs. In one or more embodiments, theCP probe 510 includes a voltage electrode 530 at the arm end-effector527 and a reference electrode 535 disposed at the outer surface of orwithin the ROV 520. In other embodiments, the voltage electrode 530 isdisposed directly at the CP probe 510. For example, the voltageelectrode 530 can be an electrically conductive tip (e.g., stainlesssteel) at an extended leg (e.g., legs 130) or an electrically conductiveportion (e.g., rim 340) and the reference electrode 535 can be asilver/silver chloride half cell or other reference electrode exposed towater. Splitting the components of the CP probe 510 in this mannerreduces the weight carried by the arm end-effector 527 and providesgreater arm mobility without sacrificing electrical performance.

During the inspection process, when the system 500 contacts theunderwater surface with the CP probe 510, a CP voltage measurement ismade as provided elsewhere herein. A signal is then sent from the CPprobe 510 along a cable within the robotic arm 525 to the ROV 520 wherethe signal is processed by a signal conditioner 540 to convert the rawelectrical signals into a coherent form for output, such as in the formof a DC signal, as is known in the art. At the same time, the referenceelectrode 535, which is exposed to seawater and having a known electrodepotential, makes a reference voltage measurement to the water andtransfers a corresponding signal to the signal conditioner 540 to beprocessed in the same manner as the CP voltage signal. The signalconditioner 540 then calculates the differential voltage between the CPprobe 510 and the reference electrode 535. The differential voltageoutput from the signal conditioner 540 is then transmitted as input to adata acquisition unit 545 where the voltage at the inspection surfacecan be recorded, reviewed, and analyzed. For example, the differentialvoltage is converted to a suitable digital or analog signal that can beprocessed and visualized to a user.

The mechanical aspects of ROV robotic arms (e.g., robotic arm 405,robotic arm 525) can also be improved in various ways. In one or moreembodiments, floatation aiding material can be added near an arm-endeffector to make the arm neutrally buoyant and to negate weight effectson the arm motors. In one or more embodiments, floatation aidingmaterial can be integrated with an integrated probe or probe system asdescribed elsewhere herein. Floatation aiding material can take the formof syntactic foam or floats made from, for example, polyurethaneelastomers or resin and hollow glass microspheres. Other floatation aidscan include umbilical buoyancy cords or the like.

Marine life growth at the inspection surface is a challenge to theefficacy of the system to take CP and UT measurements. It is thereforepreferable to remove marine growth from the inspection surface beforetaking any measurements. In one or more embodiments, the integratedprobe systems described herein can include cleaning systems mounted atthe probe system. The cleaning systems can be placed at the arm-endeffector of an ROV, such as at an attachment point. The addition of acleaning system allows for simultaneous spot cleaning (of marine life onthe underwater surface) and improved UT reading acquisition andmeasurement reliability upon contact. The cleaning systems can includeconventional ROV cleaning tools such as water jet nozzles, cavitationjet nozzles, sand blasters or rotating brushes.

In one or more embodiments, the integrated probe systems describedherein can include force or proximity sensors. A force sensor or aproximity sensor (e.g., infrared or acoustic) built in the integratedsensor body (e.g., at an attachment point, at an outer gimbal or aninner gimbal, or other position near to the CP and UT probes) can beused to aid in positioning the end effector on the targeted inspectedsurface to avoid harming the probe and/or the surface.

Notably, the figures and examples above are not meant to limit the scopeof the present application to a single implementation, as otherimplementations are possible by way of interchange of some or all of thedescribed or illustrated elements. Moreover, where certain elements ofthe present application can be partially or fully implemented usingknown components, only those portions of such known components that arenecessary for an understanding of the present application are described,and detailed descriptions of other portions of such known components areomitted so as not to obscure the application. In the presentspecification, an implementation showing a singular component should notnecessarily be limited to other implementations including a plurality ofthe same component, and vice-versa, unless explicitly stated otherwiseherein. Moreover, applicants do not intend for any term in thespecification or claims to be ascribed an uncommon or special meaningunless explicitly set forth as such. Further, the present applicationencompasses present and future known equivalents to the known componentsreferred to herein by way of illustration.

The foregoing description of the specific implementations will so fullyreveal the general nature of the application that others can, byapplying knowledge within the skill of the relevant art(s) (includingthe contents of the documents cited and incorporated by referenceherein), readily modify and/or adapt for various applications suchspecific implementations, without undue experimentation, withoutdeparting from the general concept of the present application. Suchadaptations and modifications are therefore intended to be within themeaning and range of equivalents of the disclosed implementations, basedon the teaching and guidance presented herein. It is to be understoodthat the phraseology or terminology herein is for the purpose ofdescription and not of limitation, such that the terminology orphraseology of the present specification is to be interpreted by theskilled artisan in light of the teachings and guidance presented herein,in combination with the knowledge of one skilled in the relevant art(s).

While various implementations of the present application have beendescribed above, it should be understood that they have been presentedby way of example, and not limitation. It would be apparent to oneskilled in the relevant art(s) that various changes in form and detailcould be made therein without departing from the spirit and scope of theapplication. Thus, the present application should not be limited by anyof the above-described example implementations.

What is claimed:
 1. An integrated probe suitable for performing cathodicprotection voltage readings and ultrasonic testing thicknessmeasurements at an underwater surface substantially simultaneously,comprising: an outer gimbal having a front surface and a rear surface;an inner gimbal coupled to the outer gimbal to provide at least onedegree of freedom, the inner gimbal having a front surface defining acavity therein, and the inner gimbal shaped to define one or moreingresses that pass crosswise between the front and rear surfaces of theinner gimbal; a sensor housing seated in the cavity of the inner gimbal;an ultrasonic probe disposed within the sensor housing, the ultrasonicprobe having a transducer crystal and a flexible membrane arranged aboutthe transducer crystal, and a couplant disposed within a gap between theflexible membrane and the transducer crystal; and one or more legs, eachhaving an electrically conductive tip and a subsea housing containing areference electrode, each leg extending longitudinally away from theouter gimbal via the one or more ingresses and arranged about theultrasonic probe, wherein the one or more legs are passively adjustablein response to a force imparted when the one or more legs contact theunderwater surface.
 2. The integrated probe according to claim 1,wherein the one or more ingresses are defined by the inner gimbal to beindentations formed along a circumference of the inner gimbal.
 3. Theintegrated probe according to claim 1, wherein the one or more ingressesdefined by the inner gimbal to be apertures transversely formed througha cross-section of the inner gimbal.
 4. The integrated probe accordingto claim 1, wherein at least one leg passes through an ingress definedby the inner gimbal along a circumference of the inner gimbal, and atleast one leg passes through an ingress defined by the inner gimbal asan aperture transverse to the inner gimbal.
 5. The integrated probeaccording to claim 1, further comprising an articulated carrier having afirst end integrally formed with the rear surface of the inner gimbaland a ball caster disposed at a second end, wherein the ball castercouples to the outer gimbal to provide the at least one degree offreedom to the inner gimbal.
 6. The integrated probe according to claim5, wherein the articulated carrier is conically shaped, in which thefirst end tapers toward the second end.
 7. The integrated probe of claim5, the outer gimbal being a static base defining a c-channel groovesized and shaped to couple with the ball caster.
 8. The integrated probeaccording to claim 1, wherein the electrically conductive tip is made ofstainless steel.
 9. The integrated probe according to claim 1, whereinthe outer gimbal includes a c-channel groove centrally formed at thefront surface of the outer gimbal.
 10. The integrated probe according toclaim 1, wherein the one or more legs are arranged about the ultrasonicprobe as two pairs of diametrically opposed legs.
 11. The integratedprobe according to claim 1, wherein the at least one degree of freedomis provided by one or more rotational joints coupling the inner gimbalto the outer gimbal.
 12. The integrated probe according to claim 1,wherein the at least one degree of freedom is provided by one or morerotational joints coupling the outer gimbal to an external carrier. 13.An integrated probe suitable for performing cathodic protection voltagereadings and ultrasonic testing thickness measurements substantiallysimultaneously, comprising: an ultrasonic sensor body; an ultrasonictesting cable disposed at a first end of the ultrasonic sensor body; anultrasonic probe disposed at a second end of the ultrasonic sensor body;a housing defining an aperture therethrough, wherein the aperture iscentrally located in the housing and wherein the ultrasonic probe isseated in the aperture, the housing further including an electricallyconductive portion; and conductive leads connected to and extending fromthe electrically conductive portion.
 14. The integrated probe accordingto claim 13, wherein the ultrasonic probe comprises an ultrasonicelement and a flexible membrane adjacently spaced about the ultrasonicsensor body to define a gap between the ultrasonic element and theflexible membrane, wherein the gap is filled with a couplant.
 15. Theintegrated probe according to claim 13, wherein the housing is entirelyelectrically conductive.
 16. A system for performing cathodic protectionvoltage readings and ultrasonic testing thickness measurements at anunderwater surface substantially simultaneously, comprising: a remotelyoperated underwater vehicle having a measuring arm; an end effectordisposed at a free end of the measuring arm; an integrated probe formeasuring cathodic protection voltage and ultrasonic testing thicknessmeasurement coupled to the end effector, wherein the integrated probeincludes: an outer gimbal having a front surface and a rear surface; aninner gimbal coupled to the outer gimbal to provide at least one degreeof freedom, the inner gimbal having a front surface defining a cavitytherein; a sensor housing seated in the cavity of the inner gimbal; anultrasonic probe disposed within the sensor housing, in which theultrasonic probe includes a flexible membrane arranged about atransducer crystal such that a gap is defined therebetween and filledwith a couplant; and a voltage electrode communicatively coupled to areference electrode, wherein the voltage electrode is disposed at anelectrically conductive portion of the inner gimbal, and the referenceelectrode is disposed within the remotely operated underwater vehicle.17. The system according to claim 16, wherein the reference electrode isa silver/silver chloride half cell.
 18. The system according to claim16, wherein the inner gimbal is shaped to define one or more ingressesthat pass crosswise between the front and rear surfaces of the innergimbal, and the electrically conductive portion comprises one or morelegs, each having an electrically conductive tip and extendinglongitudinally away from the outer gimbal via the one or more ingressesand arranged about the ultrasonic sensor, wherein the one or moreelectrically conductive legs are passively adjustable.
 19. The systemaccording to claim 18, wherein the voltage electrode is one or more ofthe electrically conductive tips of the one or more legs.
 20. The systemaccording to claim 16, further comprising a signal processorcommunicatively coupled to a data acquisition unit, wherein both aredisposed within the remotely operated underwater vehicle, and whereinthe signal conditioner is also communicatively coupled to the integratedprobe.
 21. A method of performing cathodic protection voltage readingsand ultrasonic testing thickness measurements on an underwater surfacewith an integrated probe having an ultrasonic probe and at least one legwith an electrically conductive tip, comprising: positioning a remotelyoperated vehicle, having at least one robotic arm with an arm endeffector disposed at a free end of the robotic arm and the integratedprobe coupled to the arm end effector, in proximity to the underwatersurface; contacting the underwater surface with the integrated probe;orienting the integrated probe transverse to the underwater surface suchthat the ultrasonic probe and the at least one leg with an electricallyconductive tip contacts the underwater surface; measuring, by the atleast one leg, a voltage at the underwater surface; measuring, by theultrasonic probe, a thickness of the underwater surface; processing, bya signal conditioner housed within the remotely operated vehicle, thevoltage and the thickness of the underwater surface to produce a datafile; transmitting the data file to a data acquisition unit housedwithin the remotely operated vehicle; and processing, by the dataacquisition unit, the data file to record, review, or analyze thevoltage and thickness of the underwater surface.
 22. An integrated probesuitable for performing cathodic protection voltage readings andultrasonic testing thickness measurements at an underwater surfacesubstantially simultaneously, comprising: a probe carrier having atleast one degree of freedom relative to a static base, the probe carrierhaving a rear surface coupled to the static base and a front surfacehaving an electrically conductive portion and defining a cavity therein;a sensor housing seated in the cavity of the probe carrier; and anultrasonic probe disposed within the sensor housing, the ultrasonicprobe having a transducer crystal and a flexible membrane arranged aboutthe transducer crystal, and a couplant disposed within a gap between theflexible membrane and the transducer crystal.
 23. The integrated probeof claim 22, the electrically conductive portion comprising one or morelegs arranged about the ultrasonic probe, each leg having anelectrically conductive tip and a subsea housing containing a referenceelectrode, and extending longitudinally away from the probe carrier,wherein the one or more legs are passively adjustable in response to aforce imparted when the one or more legs contact the underwater surface.